This chapter begins with an exhaustive coverage of the fundamental epidemiological concepts essential for understanding the epidemiology of TB, basic definitions, their relevance and significance. Experimental animal models of pulmonary TB, various models of TB epidemic in humans are described in detail. Landmark studies assessing TB problem in India are presented in detail and the burden of TB problem in India is presented meticulously, in detail. The epidemiological trend of TB in India is traced. Future directions for epidemiological evaluation are presented.